Pen



Dec. 26, 1967 K. T. BLEUER PEN ' Filed Oct. 18, 1965 v if ow Y;

United States Patent My invention relates to writing instruments and more particularly to pens using liquid ink.

It is an object of the invention to provide an improved pen with a ball point that uses liquid ink. More particularly, it is an object to provide an improved pen of this type which is so constructed that writing pressure on the ball of the pen has the effect of forcing ink around the ball whereby the ink is available for transfer by the ball on to the writing surface. Still more particularly, it is an object to provide such a pen using a cylindrical ink cartridge with pressure being applied onto the disc-like end of the cartridge due to the writing pressure on the ball tip of the pen so that the end of the cartridge functions as a small piston and thereby forces ink around and on to the ball. It is also an object to provide a first valve in such a pen which will allow ink to flow from the cartridge to the ball but not in the reverse direction and to provide :a second valve which will allow air to vent into the pen between the first valve and the cartridge, so that air need not travel around the ball back into the pen to make up for the ink that is used in writing.

The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above stated objects and such other objects as will be apparent from the following description of a preferred embodiment of the invention, illustrated with reference to the accompanying drawing, wherein:

FIG. 1 is a longitudinal sectional view of a pen embodying the principles of the invention;

FIG. 2 is a partial longitudinal sectional view of the pen taken on an enlarged scale;

FIG. 3 is a sectional view taken on line 33 of FIG. 2;

FIGS. 4 and 5 are plan views of two rubber valve elements incorporated in the pen and taken respectively on lines 44 and 5-5 of FIG. 2; and

FIG. 6 is a sectional view on a further enlarged scale taken on line 6-6 of FIG. 2.

Like characters of reference indicate like parts in the sever-a1 views.

Referring now to the drawing, the illustrate'd pen may be seen to comprise a tubular barrel 10 having a cylindrical cavity 11 therein. A tubular barrel end portion 12 is screwed into the barrel 10, and the portion 12 has a cylindrical cavity 13 therein. A plunger 14 is slidably dis posed in the cavity 13 and has a tip 15 screwed onto it. The tip 15 is formed with a cylindrical cavity 16 therein, and a bushing 17 is press fitte'd into the tip 15. A tube 18 is press fitted into the bushing 17 and has a 'ball 19 rotatably disposed in a socket 20 tube 18.

A cylindrical ink cartridge 21 is disposed in the barrel cavity 11 and comprises two disc-like ends 22 and 23. The

cartridge is made of relatively thin, somewhat flexible,

plastic material, such .as polyethylene, for example, and the disc-like ends 22 and 23 are substantially identical and of thin, substantially uniform thickness material. A shoulder 24 is provided at the end of the cavity 11, and a dished, rigid thrust element 25 rests on the shoulder and is disposed between the shoulder and the end 23 of the cartridge 21 and has its center portion in contact with the center portion of the cartridge end 23.

The plunger 14 is formed with an internal cavity 26, and a tube 27 extends longitudinally through the plunger 14 and has an internal duct 28 that connects with the provided in the end of the v cavity 26. The tube 27 has a reduced diameter portion 29 that is press fitted into the plunger 14, and the portion 29 terminates with a shoulder 30 formed on the tube 27. A thin metal disc 31 is disposed between the shoulder 30 and the adjacent end of the plunger 14. The tube 27 is provided with a biased or slanted end 32 so as to, in eifect, sharpen the tube 27 on one side.

The plunger 14 is provided with a slot 33 therethrough, and two rectangular rubber valve elements 34 and 35 and a rectangular rigid metal separator 36 are disposed in the slot 33. The valve elements 34 and 35 are preferably held in compression by the sides of the slot 33 so as to seal them with respect to the sides of the slot and with respect to the separator 36. The rubber element 34 is provided with a valve flap 37 cut into it and is also provided with an opening 38 through it. The rubber element 35 has a similar valve flap 39 in it and has .an opening 40 through it. The separator 36 is provided with two openings 41 and 42 through it. The opening 41 is in registry with the opening 38, and the opening 40 in the valve element 35 is in registry with the opening 42 in the separator 36 and is also in registry with an opening 43 in the plunger 14 which terminates between the end portion 12 and the tip 15.

A rubber washer 44 is provided between the end of the plunger 14 and the end of the cavity of the tip 15 into which the plunger is screwed. The washer 44 is held in compressed condition by the surrounding parts so as to seal the end of the cavity 26. A duct 45 extends through the plunger 14, the washer 44 and the tip 15. The duct 45 is similar in cross section to the portion of the cavity 26 overlying the valve element 34 and, like the latter, extends longitudinally of the pen. The duct 45 in the tip 15 enlarges into the cylindrical cavity 16 and is in communication with the bore 46 in the tube 18. The ball 19 has a snug but rotating fit with the sides of the socket 20, and a small bypass duct 47 is provided in the tube 18 around the ball 19.

In order to use the pen, a cartridge having liquid ink therein must first be put into the pen; and this may be done by slipping a cartridge 21 into the cavity 11 of the barrel 1% with the barrel end portion 12 being unscrewed from the barrel 10. Under these conditions, the cartridge end 23 rests on the thrust element 25, and the end portion 12 is screwed into the barrel so that the parts 10 and 12 are fully joined as illustrated in the drawing. During an initial part of the screwing of the end portion 12 into the barrel 10, the pointed tip of the tube 27 provided by the slanted end 32 makes contact with the end 22 of the cartridge 21 [and penetrates the cartridge end 22, and as the end portion 12 is screwed further into the illustrated position in the barrel 10, the larger diameter portion of the tube 27 penetrates the end 22 of the cartridge 21 and enters the cartridge 21 into its illustrated position.

The pen, like most pens, is used in a more or less upright position with the writing tip down, and the ink in the cartridge 21 tends to flow through the duct 28 of the tube 27 downwardly into the cavity 26, while the air initially in the cavity 26 flows through the duct 28 into the cartridge 21. In order to bring the ink to the writing point 19, the pen is repeatedly forced down on the writing surface; and, on each such action, the cartridge end 23 is depressed in the center and bowed inwardly by the rigid thrust element 25, which bears on the center of the cartridge end 23. On each such action, the plunger 14 is moved into the pen barrel 10 slightly, and the cartridge 21 as a whole means slightly upwardly in the cylindrical cavity 11. The cartridge end 22 is supported by and bears on the metal disc 31 which in turn is supported by and bears on the upper end of the plunger 14, so that the tip 15, the plunger 14 and the cartridge 21 (with the exception of the center of the cartridge end 23 which bears on the thrust element 25) all move upwardly with respect to the barrel and the barrel end portion 12 which are in the grasp of the writer and which are forced downwardly by him to cause the ball 19 to bear forcefully on the Writing surface. On each such action by the writer in forcing the tip 19 on the writing surface, the cartridge end 23 thus functions as a piston and forces the liquid ink into the cavity 26. The ink so forced into the cavity 26 moves through the registering openings 38 and 41 and moves the valve flap 39 slightly off the opening 41 against the inherent resilient action of the rubber valve element 35, so that a small amount of ink corresponding to the movement of the cartridge end 23 moves around the valve flap 39 into the duct 45. The cartridge end 23 is somewhat flexible and returns the tip 15 and plunger 14 to their original positions with respect to the barrel 10 and barrel portion 12 when the writer lifts the ball 19 off of the writing surface. A succession of such movements in forcing the tip 19 on the writing surface thus fills up the duct 45 and bore 46 and forces ink around the ball 19 and thus on the Writing surface. After the duct 45 and bore 46 have been filled with ink, each time the pen is used, the user instinctively uses some pressure in writing; and this pressure is exerted on the cartridge end 23 as above described and forces ink around the valve flap 39, into the duct 45 and bore 46, and around the ball 19, so that there is sufiicient ink for writing purposes. The ink in flowing around the ball flows particularly through the by-pass duct 47, so that the ball, in being rotatively disposed in the socket 20, does not stop the flow of ink on to the exposed surface of the ball.

The valve flap 37 functions to move off the opening 42 of the separator 36 against the resilient action of the rubber valve element 34, so as to admit air into the cartridge 21 through the openings 43, 40 and 42 whenever there is a partial vacuum in the cartridge 21 due to ink being forced from the cartridge by the movements of the cartridge end 23 functioning as a piston. Since the openings 43, 40 and 42 open directly into the cavity 26 and are closed only by the valve flap 37, there is no necessity for air to return to the cartridge 21 around the ball 19 which would normally be prevented by the small size of the ducts 47 and 46, hearing in mind that the liquid ink has substantial viscosity.

The pen above described advantageously uses the end of a cartridge, which is replaceable for replacing the ink supply and which is made throughout of substantially the same thickness yieldable plastic material, as a piston for forcing ink around the writing ball of the pen. Advantageously, the air that replaces the ink that is pumped out of the cartridge by the piston action of the cartridge end 23 passes directly into the cavity 26 rather than around the ball 19 which would impede the passage in opposite directions of the ink supplied to the exposed writing surface of the ball and the air that must replace the ink used from the cartridge. It will be noted that the valve flaps 39 and 37 cooperate together in preventing the return flow of ink from the duct 45 to the cavity 26 when the pressure on the ball is released and in preventing the flow of ink from the cavity 26 out through the air intake openings 42, 40 and 43 when the cartridge end 23 operates to put pressure on the ink as pressure is put on the writing ball 19 by the writer. The valve flap 39 prevents the return flow of ink to the cavity 26 by closing the opening 41 due to the resilient tendency of the valve element 35 to return to flat condition and due to the partial vacuum in the duct 26 when pressure on the ball 19 and cartridge end 23 is released; and ink pressure in the duct 26 as well as the resilient tendency of the valve element 34 cause the valve flap 37 to close the opening 42 except when there is a partial vacuum in the duct 26.

I wish it to be understood that the invention is not to be limited to the specific constructions and arrangements shown and described, except only insofar as the claims may be so limited, as it will be understood to those skilled in the art that changes may be made without departing from the principles of the invention.

I claim:

1. A pen comprising an exterior barrel adapted to be grasped by the writer in writing with the pen, a cartridge for liquid ink within said barrel, a pen tip which carries a ball rotatively mounted therein for contact with a writing surface during use of the pen and which is mounted for slight longitudinal movement within said barrel, means providing an ink duct connecting the interior of said cartridge with said ball for providing ink to the ball for writing purposes, said cartridge comprising a barrel portion and a disc-like end remote from the end of said barrel carrying said pen tip and joined at its edges to said barrel portion, said disc-like end being of thin, relatively flexible sheet material of substantially uniform thickness axially of said banrel portion for the entire internal cross sectional area of said barrel portion where the edges of said disc-like end are joined to said barrel portion, and thrust means carried by said barrel and elfective on the center portion of said disc-like end for depressing said disc-like end when writing pressure is put on said ball by the user so that the inward movement of said disc-like end forces ink from said cartridge and through said duct to said ball.

2. A pen comprising an exterior barrel adapted to be grasped by the writer in writing with the pen, a cartridge for liquid ink within said ban-rel, a pen tip which carries a ball rotatively mounted therein for contact with a writing surface during use of the pen and which is mounted for slight longitudinal movement within said barrel, means providing an ink duct connecting the interior of said cartridge with said ball for providing ink to the ball for writing purposes, said cartridge comprising a barrel portion of sheet material having an edge remote from the end of said barrel carrying said pen tip and a disclike end also remote from said last mentioned end of said barrel, said disc-like end being of thin, relatively flexible sheet material of substantially uniform thickness axially of said barrel portion and having substantially flat internal and external surfaces for the entire internal cross sectional area of said barrel portion at its said edge and said disclike end being joined at its edges to said edge of said barrel portion, and thrust means carried by said barrel and effective on the center portion of said disc-like end for depressing said disc-like end when writing pressure is put on said ball by the user so that the inward movement of said disc-like end forces ink from said cartridge and through said duct to said ball.

3. A pen comprising an exterior barrel adapted to be grasped by the writer in writing with the pen, a cartridge for liquid ink within the barrel, a pen tip which carries a ball rotatively mounted therein for contact with a writing surface during use of the pen and which is mounted for slight longitudinal movement within said barrel, means 'providing an ink duct connecting the interior of said cartridge with said ball for providing ink to the ball for Writing purposes, said cartridge having an end remote from the end of said barrel carrying said pen tip which is slightly flexible, thrust means carried by said barrel and effective on the center portion of said last mentioned cartridge end for depressing said cartridge end when Writing pressure is put on said ball by the user so that the inward movement of the cartridge end forces ink from said cartridge and through said duct to said ball, and valve means effective for venting air into said duct between said ball and said cartridge and effective for preventing the flow of ink through the valve means when said thrust means is effective for forcing ink from the cartridge to said ball.

4. A pen as set forth in claim 3, and additional valve means effective for preventing the return flow of ink through said duct from said ball to said first named valve means and to said cartridge.

5. A pen comprising an exterior banrel adapted to be grasped by the writer in writing with the pen and having a pen tip which carries a ball rotatively mounted therein for contact with a writing surface during use of the pen, said barrel having an internal cavity adapted to receive an ink cartridge therein which has a relatively flexible end located remotely from said pen tip, thrust means carried by said barrel in the end of said cavity remote from said tip so as to be effective on the flexible end of the cartridge, means providing an ink duct from said cavity and an ink cartridge therein to said ball, said tip being mounted for slight longitudinal movement in said barrel so that writing pressure on said ball is transmitted through the barrel and said thrust means to the flexible end of the cartridge so as to force ink from the cartridge through said duct to said ball, and valve means for venting air into said duct between said ball and said cavity and effective for preventing the flow of ink through the valve means when said thrust means is effective to force ink from a cartridge through said duct to said ball.

6. A pen as set forth in claim 5, and additional valve means effective for preventing the return flow of ink through said duct from said ball to said first named valve means and to said cavity.

7. A pen as set forth in claim 5, said barrel comprising a barrel end portion and a main barrel portion having a screw threaded engagement to allow a cartridge to be inserted into said barrel cavity when the end barrel portion is unscrewed from said main barrel portion, and said tip comprising a plunger portion which is longitudinally movable in said barrel end portion due to writing pressure on said ball.

8. A pen as set forth in claim 7, said duct providing means including a tube carried by and fixed with respect to said plunger portion and adapted to penetrate an end of a cartridge within said cavity as said main barrel portion and said end barrel portion are screwed together.

9. A pen as set forth in claim 6, said valve means comprising a pair of flaps of rubber-like material and means providing an opening adapted to be closed by each of said flaps.

10. A pen as set forth in claim 6, said valve means comprising a pair of pieces of rubber-like material and a separator of rigid material between said pieces, said separator having a pair of spaced openings through it and each of said pieces of rubber-like material having a movable tlap portion in it adapted to be disposed over and close one of said openings.

11. A pen as set forth in claim 6, said tip comprising a plunger portion which is longitudinally movable in said barrel and having a slot therein, and said valve means comprising a pair of pieces of rubber-like material and a separator of rigid material between said pieces and all located in said sl-ot, said separator having a pair of spaced openings through it and each of said pieces of rubber-like material having a movable flap portion in it adapted to be disposed over and to close one of said openings.

12. A pen as set forth in claim 11, said slot extending longitudinally of said plunger portion and said pieces of rubber-like material being compressed into the slot and being thereby sealed with respect to the sides of the slot.

References Cited UNITED STATES PATENTS 2,870,742 1/ 1959 Hackmyer --45.4

FOREIGN PATENTS 167,75 8 2/ 1951 Austria. 633,880 12/ 1949 Great Britain. 926,054 4/ 1955 Germany. 446,795 3/ 1949 Italy.

LAWRENCE CHARLES, Primary Examiner. 

1. A PEN COMPRISING AN EXTERIOR BARREL ADAPTED TO BE GRASPED BY THE WRITER IN WRITING WITH THE PEN, A CARTRIDGE FOR LIQUID INK WITHIN SAID BARREL, A PEN TIP WHICH CARRIES A BALL ROTATIVELY MOUNTED THEREIN FOR CONTACT WITH A WRITING SURFACE DURING USE OF THE PEN AND WHICH IS MOUNTED FOR SLIGHT LONGITUDINAL MOVEMENT WITHIN SAID BARREL, MEANS PROVIDING AN INK DUCT CONNECTING THE INTERIOR OF SAID CARTRIDGE WITH SAID BALL FOR PROVIDING INK TO THE BALL FOR WRITING PURPOSES, SAID CARTRIDGE COMPRISING A BARREL PORTION AND A DISC-LIKE END REMOTE FROM THE END OF SAID BARREL CARRYING SAID PEN TIP AND JOINED AT ITS EDGES TO SAID BARREL PORTION, SAID DISC-LIKE END BEING OF 